1. Field of the Invention
The present invention relates to school desks and chairs adjustable in height and in particular to legs for desk which can vary in length.
Furniture for primary schools requires considerable storage space because the pupils and students using them do not have, year after year, the same stature. Furthermore, the same school may have different repartition of pupils among the different grades.
It is an object of the invention to change the height of desks and chairs so that a minimal number of such pieces of furniture be needed to accommodate a plurality of the corresponding numbers of students regardless of their height.
It is another object of this invention to adapt existing equipment to meet the requirements of adjustability. The present invention can be implemented by cutting the legs of presently available desks and chairs and providing suitable extentions for them.
2. Prior Art
The search performed by the applicants has revealed two Canadian patents directed to means for adjusting the height of school desks. In Canadian patent No. 739,251, a pair of telescopic tubes is described with a displacing means consisting of a combination of a toothed rack and ratched wheel mounted on the tubes to adjust the height of the desk and to lock the tubes in a fixed position.
In Canadian patent No. 764,304 the school desk is vertically adjustable. The legs of the desk consist of two coaxial tubes which are vertically adjustable by means of a screw spindle and a pair of bevelled pinions fixed at the upper end of the screw spindle.
The prior art discloses complex mechanical arrangements which are expensive and do not allow the conversion of conventional wooden desks into desks having adjustable heights.